powerpoints

Here is an online presentation on how to count atoms:
http://www.slideshare.net/FJHScience/counting-atoms-14627676






The Science Techbook has a great section on it with many videos and activities.
https://app.discoveryeducation.com/player/view/assetGuid/8FEDCCB3-1453-47FB-9C2F-4C7DD09480C8

Try J.J. Thomson's cathode ray tube experiment!
https://app.discoveryeducation.com/player/view/assetGuid/70F5EE14-1FA9-4622-8B9A-04699C875DED

This is a 50-minute video that does a great job in explaining in a simple and interesting way the history of the atom and the people behind them. It is captioned!
Atom: The Key to the Cosmos